Switchable luminance led light bulb

ABSTRACT

A switchable luminance LED light bulb, including embodiments that may be used with any common commercial fitting.

RELATIONSHIP TO OTHER APPLICATIONS

The present application claims priority to, and the benefit of thefollowing applications that are entirely incorporated by reference tothe fullest extent allowable by law: U.S. application Ser. No.6,165,6021 filed 6 Jun. 2012 titled ‘Switchable LED Light Bulb’ and U.S.application Ser. No. 61,667,982 filed 4 Jul. 2012 titled ‘SwitchableLuminance LED Light Bulb’.

FIELD OF THE INVENTION

The presently disclosed subject matter is directed towards LED-typelight bulbs. More particularly the presently disclosed subject matterrelates to LED-type light bulbs that have switch controlled illuminationintensities.

BACKGROUND OF THE INVENTION

While white light LED light bulbs have proven to be highly successfulthey have lacked one feature available in traditional incandescent lightbulbs: the ability to provide multiple light outputs from one lamp. Forexample, 3-way Edison light bulbs are widely used to provide switchablelight outputs. A 3-way Edison light bulb could use switched filaments toproduce the light output of a 100 Watt, a 200 watt or a 300 watt lightbulb. This feature has proven to be extremely popular and useful. Inview of the foregoing, white light LED light bulbs havingswitch-selectable light outputs would be useful and commerciallydesirable. Even more useful would be white light LED light bulbs havingswitch-selectable light outputs and which mate with Edison, screw orbayonet fixtures.

BRIEF SUMMARY OF THE INVENTION

The present invention provides an LED bulb (‘the device’) withswitch-selectable light outputs. The bulb may be mated with Edison,screw or bayonet types of lamp base fixtures. It is understood in thepresent disclosure that when an Edison fixture is mentioned as anexample, the applicant is only using this as an example and implicitlyincludes all other types of fixtures such as screw or bayonet types.

The invention provides a low-power, transformerless, LED light bulbpower supply capable of providing varying levels of electric currentcapable of powering variable numbers of LESd to produce proportionallyvarying levels of light. The invention allows any lamp using a standardEdison, screw bayonet type base to become an arbitrary-way lamp. This issimilar to the common ‘3-way’ lamp, but with the following keydifferences: (a) no specialty lamp is required, (b) no specialty 3-waybulb is required. The invention is different from a standard ‘dimmable’bulb. It allows for a bulb to have as many discrete light output stepsas desirable. The inventors' early prototype was capable of producinglight equivalent to a 40W or 60W incandescent bulb using a switch toselect between lighting levels. Commercially the invention allows themanufacturer to produce one design in mass quantity that will fit manyneeds. Due to the low power (below 10W) property of the LED light bulb,this invention is an appropriate replacement for almost any standardlight bulb. When any standard bulb fails it could simply be replacedwith a bulb of the invention and the user could set the desired lightingoutput at the time of installation. Therefore only one type of bulb needbe purchased to replace a range of old standard bulbs.

The present invention encompasses a switchable luminance LED light bulbdevice comprising a rectifier to rectify AC to DC, wherein the DCcurrent is fed into a switch, the switch having a single input pole andmultiple output poles and a plurality of selectable positions, whereinthe switch directs the current through one of a plurality of selectableresistors and/or capacitors corresponding to one of a plurality ofdifferent DC output currents, wherein the selected DC output current isfed into at least one of a plurality of light emitting diodes, whereinthe selected DC output current corresponds to the light output of thelight emitting diodes.

In certain embodiments the device will include a switch that can directthe current through a number of resistors, with no switchable selectionof capacitors. In other embodiments, in order to increase the range ofcurrent and therefore light output, the device includes a switchableselection of capacitors. In this embodiment, an operator may select acombination of capacitors and resistors. The capacitor switch may beplaced ‘upstream’ of the resistor switch, so that the current is firstrouted to one of a plurality of capacitors, each of which is may beassociated with two or more resistors (for example 3, 4, 5, 6 or moreresistors). Each capacitor is associated with two or more resistors soas to provide a graduated increase or decrease in current and thereforeluminescence.

A current regulating device may be integrated into the device, and maybe, in certain embodiments a step-down constant current controller. Thedevice may comprise a current-regulating device and at least onetransistor, wherein the current regulating device modulates the gate ofthe output transistor by reading the voltage, thereby regulating currentdelivered to LEDs.

In some embodiments the transistor may be, but is not necessarily, afield-effect transistor. In some embodiments it may be a MOSFET.

The present invention provides a white LED (light Emitting Diode) lightbulb having a plurality of (two or more) white LEDs for emitting light.In some embodiments the LED light bulb includes an Edison-style screwcap for screwing into an Edison style base to receive input ACelectrical power. However, the present invention is applicable to lightbulbs with other types of caps for fitting other types of bases. Adriver cover may be attached at one end to the Edison-style cap. Thedriver cover may include an opening for an actuator (any component thatmay be physically manipulated into different positions such as a switch,a slider, or a plurality of push-buttons) or a multiple-throw switch topass through the driver cover, which enables a user to change theswitched pole. In some embodiments the actuator need not be manuallyoperable by the user, but may be operable remotely through a wiredconnection or a wireless connection employing widely known circuittechnology.

A driver board retaining the switch may be at least partially locatedwithin the driver cover such that the switch passes through the opening.The driver board receives the input AC electrical power, rectifies thatinput AC electrical power into DC electrical power, and applies aconstant DC current to the array of LEDs such that the applied currentfunctionally depends on the selected pole position of the switch, andthus the light output functionally depends on the selected poleposition.

In one embodiment the invention provides an LED light bulb, comprisingone or more (in some embodiments two or more) LEDs for emitting a numberof different light outputs of different intensity, for example either afirst light output or a second light output; a cap for attaching to abase to receive input AC electrical power; a driver cover attached atone end to the cap, the driver cover having an opening through which aswitch protrudes and is accessible; and a driver board having a switchhaving at least two positions selectable by an actuator that passesthrough the opening and is accessible to a user to change the switchposition. The driver board further includes components capable ofreceiving input AC current, and rectifying the input AC current toproduce a DC current of either a first magnitude or a second magnitudeselected by the switch (pole) position.

In one embodiment the device comprises two strings of LEDs in parallel,and both strings are always powered. The current to each string isreduced in the lower lighting mode.

The DC current is applied to at least one LED wherein the LED(s) producea first lumen output when said first DC current is applied oroptionally, a second lumen output when said second DC current isapplied; and wherein both first and second DC currents are sufficient tocause said at least one LED to emit light.

In certain embodiments the switch may be switchable to two or morepositions, for example 1, 2, 3, 4, 5 or more switch positions, eachassociated with a different DC current, and therefore each associatedwith a different brightness (output value) of the one or more LEDs. Insome embodiments all positions and all DC currents are sufficient toproduce light from the LED. In other embodiments at least one positionprevents the flow of current to the LED such that the LED produces nolight (the “off” position).

Other embodiments include the LED light bulb wherein said cap is anEdison-style screw cap. Other embodiments use a non-Edison screw cap andmay be suitable for attachment to any standard or non-standardelectrical fixture. The LED may emit white light or a colored light. Thelight bulb may comprise a plurality of LEDs mounted on a light engineboard. The switch may be a multiple pole slide switch or any other typeof suitable switch including a push button, a rocker or a touchsensitive switch. The LED light bulb may include a light diffuser,and/or heat sink in thermal communication with said at least one LED.The driver board may include a switch having at least three selectablepositions corresponding to three different DC currents, or in someembodiments a switch having between, for example, two and 10 selectablepositions corresponding to between 2 and 10 different DC currents. Othernumbers of alternative positions are possible and commonly 2 or 3 switchpositions are provided. Alternatively at least 4, 5, 6 7, 10, 15, 20,25, at least 50 or more switch positions may be provided. In someembodiments the LED light bulb may have a driver board comprising aswitch having at least three selectable positions, one of whichcorresponds to an “off” position whereby no light is provided from oneor more of the LEDs.

The present invention, though apparently simple in hindsight, is bothnovel and of great commercial value, and includes several technicalfeatures that are transformative in their effect, turning a simple LEDlight into a multiple-intensity light bulb, easily switchable betweenlight intensities.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages and features of the present invention will become betterunderstood with reference to the following detailed description andclaims when taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a pictorial diagram of an LED light bulb 10 that is in accordwith the principles of the present invention;

FIG. 2 is an exploded view of the LED light bulb 10 shown in FIG. 1;

FIG. 3 is a block diagram of the mechanical system of the LED light bulb10 shown in FIGS. 1 and 2;

FIG. 4 is a block diagram of the electrical system of the LED light bulb10 shown in FIGS. 1 and 2;

FIG. 5 is a schematic diagram of the LED light bulb driver circuit 10shown in FIGS. 1 and 2. Note in FIG. 5, the switch referred to in partsof the text as part ‘32’ is actually labeled ‘SW1’. When reading ‘32’please substitute ‘SW1’;

FIG. 6 is a block diagram of the thermal path of the LED light bulb 10shown in FIGS. 1 and 2.

DETAILED DESCRIPTION OF THE INVENTION

In the figures like numbers refer to like elements throughout.Additionally, the terms “a” and “an” as used herein do not denote alimitation of quantity, but rather denote the presence of at least oneof the referenced items. All publications mentioned herein areincorporated by reference for all purposes to the extent allowable bylaw.

The presently disclosed subject matter now will be described more fullyhereinafter with reference to the accompanying drawings in which aspecific embodiment is shown. However, it should be understood that thisinvention may take many different forms and thus it should not beconstrued as being limited to the specific embodiments set forth herein.

The invention encompasses a light bulb comprised of a plurality of LEDshaving switch controlled illumination intensities.

In a broad embodiment, the invention encompasses a light bulb devicecomprising an AC electrical input, a plurality of (one or more) LEDscapable of emitting variable light intensities depending on the DC inputcurrent. The LEDs are in electrical communication with a driver board.The driver board is in communication with the AC electrical input. Thedriver board comprises a rectifier for rectifying AC current into DCcurrent, and a switch having at least two selectable positionscorresponding to a DC output of a first amperage or a second amperagecorresponding to the selected switch position. The switch directs thecurrent through one of two or more selectable resistors to provide thedesired current, that is inversely proportional to resistance for agiven voltage. The DC output amperage corresponds to the light outputintensity of the LED(s).

The switch generally has one input pole (but could in other embodimentsinclude a plurality of input poles), and generally has a plurality ofoutput poles.

The switch (“the resistor switch”) switches the current between aplurality of resistors.

The switch can take the form of a slide switch, a push-button switch, arotary switch, a pull switch, a toggle switch, a knife switch, a touchswitch, or any other multiple position switch suitable for selectingcurrent through a resistor.

In other embodiments another switch (a ‘capacitor switch’) is provided,upstream of the resistor switch, that switches the current betweenalternative capacitors. The capacitor switch can have a single input,and multiple outputs corresponding to a plurality of capacitors, forexample, 1, 2, 3, 4, 5, 6, or 7 or more capacitors. Each capacitor willbe associated with, and will conduct current to, a resistor switch,which will switch the current between a plurality of resistors, aspreviously described. In this way the range of DC current, and thereforeluminescence, in increased.

In one embodiment, two switch positions correspond to a first amperageand a second amperage wherein both amperages are sufficient to cause atleast one (or all) of the LEDs to emit light.

In another embodiment the switch comprises at least three selectableswitch positions at least two of which correspond to an amperagesufficient to cause at least one LEDs to emit light, and wherein atleast one selectable switch position corresponds to an “off” positionwherein no said LEDs emit an appreciable intensity of light visible tothe human eye in normal daylight conditions.

In certain embodiments the device of the invention includes a currentregulating device. This current regulating device may, for example, be achip (in the exemplary embodiment the inventors used an “lm 3444”) thatpulse width modulates (PWM) the gate of the output MOSFET(metal-oxide-semiconductor field-effect transistor). The IC measures thevoltage through the ISNS pin and regulates the current accordingly.

Although a MOSFET is used in the example, any transistor providing thesame functions may be used in other embodiments (e.g., an FET, a BJT oreven more crudely, anything that can produce a constant DC voltage, maybe employed).

In one embodiment a second transistor is provided that in conjunctionwith the Zener diode provides constant voltage.

An exemplary embodiment provides a switchable luminance LED light bulbdevice comprising: an AC input component in functional communicationwith a driver board, the driver board comprising a rectifier, whereinthe DC current is fed into a switch, the switch having a single inputpole and multiple output poles and a plurality of selectable positions,wherein the switch directs the current through one of a plurality ofselectable resistors corresponding to one of a plurality of different DCoutput currents, wherein the selected DC output current is fed into atleast one of a plurality of light emitting diodes, wherein the selectedDC output current corresponds to the light output of the light emittingdiodes.

The switch may be of any suitable type such as a slide switch, apush-button switch, a rotary switch, a pull switch, a toggle switch, aknife switch or a touch switch.

In some embodiments any selectable DC output current is sufficient tocause at least one of a plurality of light emitting diodes to emitlight. In other embodiments at least one selectable DC output currentcorresponds to an “off” position and is insufficient to cause at leastone of a plurality of light emitting diodes to emit light.

The device may include a current-regulating device functionallyassociated with the driver board to regulate current to the LEDs. Thecurrent-regulating device may be a current regulating integratedcircuit.

The device may include a current-regulating device and at least onetransistor, wherein the current regulating device modulates the gate ofthe output transistor (for example, but not necessarily, a MOSFET orother field-effect transistor) by measuring the voltage, therebyregulating current.

In some embodiments the device comprises at least two transistorswherein one transistor is in communication with the Zener diode so as toprovide constant voltage to the current regulating device.

Other components in various embodiments may include a noise suppressioncapacitor downstream of the AC input, and a bridge rectifier downstreamof the AC input.

Other embodiments may include voltage regulation by use of a Zenerdiode. The regulated voltage can be applied to an N-channel power MOSFETand the drain of the MOSFET may be connected to a node while the sourceconnects to the anode of a Schottky rectifier and wherein the cathode ofthe Schottky rectifier connects to a second, fixed voltage nodeconnected to a filter capacitor, wherein the second node also connectsto the input of a current regulator and to the common pole of a switchhaving a single input pole and a plurality of output poles correspondingto a plurality of resistors, wherein the current regulator is a constantcurrent controller that provides a regulated current for illuminating alight emitting diode.

Alternative commercial embodiments include a driver board ismechanically attached to a cap adapted to be releasably fitted to an ACelectrical output socket. The cap may be of any suitable type such as anEdison-style screw cap or bayonet-mount cap or any other type of cap.

In some embodiments the switch includes an actuator that is manuallyoperable, i.e. an external switch is provided by which means an operatorcan switch between intensities of illumination. The switch mayalternatively be operable remotely, either by wire or wireless means ofcontrol.

In an exemplary embodiment the device includes an AC input componentthat routes the input voltage across a noise suppression capacitor to abridge rectifier, wherein one output of the bridge rectifier goes toground while the positive output goes to a node wherein the voltage atthe node is applied to a Zener diode via a resistor to produce aregulated voltage on the gate of an N-channel power MOSFET, wherein thedrain of the MOSFET connects to the node while the source connects tothe anode of a Schottky rectifier, wherein the cathode of the Schottkyrectifier to a second, fixed voltage node connected to a filtercapacitor, wherein the second also connects to the input of a currentregulator and a switch having a single input pole and a plurality ofoutput poles corresponding to a plurality of resistors, wherein thecurrent regulator is a constant current controller that provides aregulated current for illuminating a light emitting diode.

FIG. 5 presents a schematic diagram of the electronics on the LED driverboard 16. The AC line voltage 100 is applied to input terminals 110which route the line voltage 100 across a noise suppression capacitor112 and across the input terminals of a bridge rectifier 114. One outputof the bridge rectifier 114 goes to ground 116 while the positive outputgoes to a node 118.

The voltage at the node 118 is applied to a Zener diode 120 via aresistor 122. This produces a regulated voltage on the gate of anN-channel power MOSFET 124 transistor. The drain of the MOSFET 124connects to the node 18 while the source connects to the anode of aSchottky rectifier 128. The cathode of the Schottky rectifier 128 goesto a node 130 which connects to a filter capacitor 132. The node 130 istherefore a fixed voltage node.

Note that when a “Schottky rectifier” is specified in this disclosure,any other rectifier performing the same function may be used,particularly any semiconductor diode with a low forward voltage drop anda very fast switching action.

The node 130 also connects to the Vcc input of an LM3444 currentregulator IC 134 and to the common terminal 136 of the switch 32, whichmay be a single pole double throw (SPDT) switch. Note in FIG. 5, theswitch referred to in parts of the text as part ‘32’ is actually labeled‘SW1’. When reading ‘32’ please substitute ‘SW1. Thus the single inputpole of the switch 32 controls which of its two output poles 191 and 193is selected. The current regulator IC 134 is a constant currentcontroller that regulates current for powering one or more LEDs. Theactual regulated current is controlled by the pole position of theswitch 32. The voltage on the node 130 is selectively switched by theswitch 32 between resistors 140 and 142 via poles 191, 193,respectively. While the switch 32 in the example is only a double throwswitch, in other embodiments more switching poles can be used with morecapacitors and/or resistors to achieve additional switch selectablelumens.

Having two (or greater) switch selectable DC current magnitudes reflectsa beneficial design choice characterized by both low cost and simpleuser operation. However, another useful embodiment uses a three positionillumination control switch, two positions of which select DC currentmagnitudes while the third position turns the LED light bulb 10 OFF.Another useful embodiment also uses a three position illuminationcontrol switch, but all three positions select different DC currentmagnitudes, thus allowing the illumination control switch to selectthree different illuminations. Other useful embodiments have 4 to 10 andpossibly even more illumination control switch positions that selectdifferent DC current magnitudes (including OFF) and thus theillumination control switch can select four to 10 or more differentilluminations. All of those embodiments as well as others that fallwithin the broad scope of the appended claims are encompassed by thisinvention.

The principles of the present invention are illustrated in the exemplaryembodiment shown in FIGS. 1 through 6. Referring now to FIGS. 1 and 2the present invention relates to an LED light bulb 10. The LED lightbulb 10 includes an Edison-type screw cap 12 that mates with prior artEdison-type bases. In fact, the LED light bulb 10 is configured to be adirect replacement for prior art Edison light bulbs. Thus the LED lightbulb 10 is directly useable in millions of existing applications.

Still referring to FIGS. 1 and 2, the Edison screw cap 12 connects to adriver case 14 which houses an LED driver board 16. The driver case 14connects at its other end to a heat sink 18 such that the devices on theLED driver board 16 are in thermal communication with the heat sink 18.In certain embodiments the light engine is in thermal communication withthe heat sink, and in other embodiments the driver board may not be inthermal communication with the heat sink. Attached to the other end ofthe heat sink 18 is a light diffuser 20. The light diffuser 20 covers alight engine 26 board that is in thermal communication with the heatsink 18. An actuator arm 30 of a multiple position switch 32 on the LEDdriver board 16 pass through a slot 34 that extends along the drivercase 14. Note in FIG. 5, the switch referred to in parts of the text aspart ‘32’ is actually labeled ‘SW1’. When reading ‘32’ please substitute‘SW1’.

FIG. 3 presents another mechanical view of the LED light bulb 10. FIG. 3shows the diffuser 20 as being attached to the light engine 26 by clips40. Note that clips are given as an example, but any suitable fixingdevice may be used such as screws, solder etc. Inside the light engine40 is a printed circuit board PCB 42 that holds an array of white-LEDs44. The white-LEDs 44 are arranged to emit white light into the diffuser20. Also as shown the light engine 26 is attached to the heat sink 18 byscrews 46. Note that screws are given as an example, but any suitablefixing device may be used such as clips, solder etc.

The heat sink 18 covers most of the driver casing 14. Located inside thedriver casing 14 is the LED driver board 16. As shown the LED driverboard 16 includes a bridge rectifier 52, a buck converter 54, themultiple position switch 32 and a driver IC 56, while the driver casing14 is attached to the Edison screw cap 12 by glue 60. Note that any formof fixing agent may be used.

The white-LEDs 44 operate on direct current (DC) electrical currentwhile the standard household current power is AC. Thus rectification isrequired. Furthermore, the LEDs 44 operate at relatively low voltagesand for proper operation they receive regulated DC currents supplied atappropriate low voltages. The higher the DC current the more light(lumens) and heat the white-LEDs 44 produce. The LED light bulb 10provides for two or more switch 32 selectable DC currents that areselectively applied to the white-LEDs 44 to emit light as well as forthermal heat sinks and cooling. While other configurations might includea switch that completely turns off the LEDs, in the LED light bulb 10both switch 32 positions cause light to be emitted from the white-LEDs44. Both the electrical operation and thermal paths are important. Inthe present example the LED light bulb 10 provides for two switch 32selectable DC currents, however in other embodiments, 3, 4, 5 or moreselectable DC currents may be provided by the switch.

The overall electrical path of the LED light bulb 10 is shown in FIG. 4.AC voltage 100 is input to the LED light bulb 10 and is directed to theLED driver board 16. As previously described the LED driver board 16includes the driver IC 56, the bridge rectifier 52, the buck converter54, and the switch 32. The switch 32 has multiple poles that control theDC current 104 that is applied to the light engine 26, its white-LEDs44, and its printed circuit board PCB 42. The printed circuit board 42retains the white-LEDs 44 while the amount of the applied DC currentdepends on which position of the switch is selected. Since the switch 32controls the amount of DC current it also controls the light output ofthe white-LEDs 44.

The efficiency of white light LED devices is increasing over time. Thus,the number of individual white-LEDs 44 required in a particularapplication will depend both on the amount of light output desired aswell as the efficiency of the individual LEDs 44. However, it should beunderstood that the LEDs 44 do not uniformly emit light, and that theirlumen (light) outputs are directed into the diffuser 20 which diffusesthe light in a more uniform way.

FIG. 5 presents a schematic diagram of the electronics on the LED driverboard 16. The AC line voltage 100 is applied to input terminals 110which route the line voltage 100 across a noise suppression capacitor112 and across the input terminals of a bridge rectifier 114. One outputof the bridge rectifier 114 goes to ground 116 while the positive outputgoes to a node 118.

The voltage at the node 118 is applied to a Zener diode 120 via aresistor 122. This produces a regulated voltage on the gate of anN-channel power MOSFET 124 transistor. The drain of the MOSFET 124connects to the node 118 while the source connects to the anode of aSchottky rectifier 128. The cathode of the Schottky rectifier 128 goesto a node 130 which connects to a filter capacitor 132. The node 130 istherefore a fixed voltage node.

The node 130 also connects to the Vcc input of an LM3444 currentregulator IC 134 and to the common terminal of the switch 32. Thus thesingle input pole of the switch 32 controls which of its two outputpoles is selected. The current regulator IC 134 is a constant currentcontroller that power the high power LEDs. The actual regulated currentis controlled by the pole position of the switch 32. The voltage on thenode 130 is selectively switched by the switch 32 between resistors 140and 142 via poles 191, 193, respectively. While the switch 32 is only adouble throw switch, in other embodiments more switching poles can beused with more capacitors and/or resistors to achieve additional switchselectable lumens.

The outputs of the resistors 140 and 142 (and any other lumen controlresistor that is used) are applied to the C-off input pin (pin 4 in thefigure) input of the current regulator IC 134 and to a high frequencyfilter capacitor 144. The current regulator IC 134 regulates the voltageon a gate output 150 which is applied via a resistor 152 to the gate ofan N-Channel MOSFET 158. The source of the N-Channel MOSFET 158 connectsto ground 116 via a current sense resistor 160 and to a current senseinput of the current regulator IC 134. The drain of the N-Channel MOSFET158 connects to an Driver output terminal 164 via a transient reducinginductor 166.

The LEDs 44 are series connected with the cathode end connecting to anDriver output terminal 164 and the anode end connecting to an driveroutput terminal 170. A filtering capacitor 172 also connects between theDriver output terminal 164 and the Driver output terminal 170. Connectedbetween the Driver output terminal 170 and the drain of the N-ChannelMOSFET 158 is a fast recovery diode having its cathode end connected tothe Driver output terminal 170. Connected between the Driver outputterminal 170 and the node 118 is a Schottky diode 172 having its cathodeconnected to the Driver output terminal 170.

The current-regulating device regulates the current applied to the LEDs.The current-regulating device in the example is specified as regulatingabout 175 mA to about 320 mA of DC current. In some alternativeembodiments the device may draw between 10 mA and 100,000 mA, forexample between 100 and 4000 mA, or between 100 and 750 mA, or between500 and 1000 mA, or between 500 and 5000 mA. The LED light bulb may beconfigured to have similar light outputs to incandescent bulb of 1W, 5W,10W, 25W, 50W, 75W, 100W, 200W, 500W, 1000W, 3000W and 10,000W or evenmore.

In operation, the bridge rectifier 114 places a rectified voltage on thenode 118. The current through the LEDs 44 passes through the N-ChannelMOSFET 158, with that current being regulated by the voltage applied bythe current regulator IC 134 to the gate of the N-Channel MOSFET 158.That current is sensed by the current regulator IC 134 by its monitoringof the voltage drop across the sensing resistor 160. The desired currentdepends on the current through either the resistor 140 or 142, dependingon which is selected by the pole position of the switch 32. Once theresistor 140, 142 is selected the current regulator IC 134 regulates thecurrent through the LEDs 44.

The LEDs 44 in the LED light bulb 10 are connected as twoseries-parallel strands of LEDs. The leading cathode input end of eachstrand is connected to the Driver output terminal 164 and the trailinganode output end of each strand is connected to the Driver outputterminal 170.

Referring now to FIG. 6, the LEDs 44 generates heat. That heat istransferred to the PCB 42, which is composed of FR4 material with copperplanes on top and bottom connected by electrically-isolated,thermally-conductive through-hole vias. From the PCB, heat is conductedto the heat sink 18 which radiates heat to the ambient air 200. In otherembodiments, metal-core PCBs may be used to allow for heat transference.

Therefore, it is to be understood that while the figures and the abovedescription illustrate the present invention, they are exemplary only.They are not intended to be exhaustive or to limit the invention to theprecise forms disclosed, and obviously many modifications and variationsare possible in light of the above teaching. Others who are skilled inthe applicable arts will recognize numerous modifications andadaptations of the illustrated embodiments that remain within theprinciples of the present invention. Therefore, the present invention isto be limited only by the appended claims.

1. A switchable luminance LED light bulb device comprising: an AC inputcomponent in functional communication with a driver board, the driverboard comprising a rectifier, wherein the DC current is fed into aswitch, the switch having a single input pole and multiple output polesand a plurality of selectable positions, wherein the switch directs thecurrent through one of a plurality of selectable capacitors and/orresistors corresponding to one of a plurality of different DC outputcurrents, wherein the selected DC output current is fed into at leastone of a plurality of light emitting diodes, wherein the selected DCoutput current corresponds to the light output of the light emittingdiodes.
 2. The device of claim 1 wherein any selectable DC outputcurrent is sufficient to cause at least one of a plurality of lightemitting diodes to emit light.
 3. The device of claim 1 wherein at leastone selectable DC output current corresponds to an “off” position and isinsufficient to cause at least one of a plurality of light emittingdiodes to emit light.
 4. The device of claim 1 further comprising aswitch having a plurality of output poles each connected to a differentcapacitor, wherein the current from the capacitor is subsequentlyconducted to a switch having a plurality of output poles each connectedto a different resistor, wherein the combination of capacitor andresistor selected corresponds to a selected DC output current thatcorresponds to the light output of the light emitting diodes.
 5. Thedevice of claim 1 further comprising a current regulating devicefunctionally associated with the driver board.
 6. The device of claim 5wherein the current regulating device is a current regulating integratedcircuit.
 7. The device of claim 5 further comprising a currentregulating device and at least one transistor, wherein the currentregulating device modulates the gate of the output transistor bymeasuring the voltage, thereby regulating current.
 8. The device ofclaim 7 wherein the transistor is a MOSFET.
 9. The device of claim 1comprising at least two transistors wherein one transistor is incommunication with the Zener diode so as to provide constant voltage tothe current regulating device.
 10. The device of claim 1 wherein theswitch is selected from a slide switch, a push-button switch, a rotaryswitch, a pull switch, a toggle switch, a knife switch, a wirelessswitch and a touch switch.
 11. The device of claim 1 further comprisinga noise suppression capacitor downstream of the AC input.
 12. The deviceof claim 1 further comprising a bridge rectifier downstream of the ACinput.
 13. The device of claim 12 wherein voltage is regulated by use ofa Zener diode.
 14. The device of claim 13 wherein the regulated voltageis applied to a transistor and the drain of the transistor connects to anode while the source connects to the anode of a rectifier and whereinthe cathode of the rectifier connects to a second, fixed voltage nodeconnected to a filter capacitor, wherein the second node also connectsto the input of a current regulator and to the common pole of a switchhaving a single input pole and a plurality of output poles correspondingto a plurality of capacitors and/or resistors, wherein the currentregulator is a constant current controller that provides a regulatedcurrent for illuminating a light emitting diode.
 15. The device of claim1 wherein the driver board is mechanically attached to a cap adapted tobe releasably fitted to an AC electrical output socket.
 16. The deviceof claim 15 wherein said cap is an Edison-style screw cap.
 17. Thedevice of claim 15 wherein said cap is bayonet-mount cap.
 18. The deviceof claim 15 wherein the switch includes an actuator that is manuallyoperable
 19. The device of claim 1 wherein the AC input component routesthe input voltage across a noise suppression capacitor to a bridgerectifier, wherein one output of the bridge rectifier goes to groundwhile the positive output goes to a node wherein the voltage at the nodeis applied to a Zener diode via a resistor to produce a regulatedvoltage on the gate of an N-channel power MOSFET, wherein the drain ofthe MOSFET connects to the node while the source connects to the anodeof a Schottky rectifier, wherein the cathode of the Schottky rectifierto a second, fixed voltage node connected to a filter capacitor, whereinthe second also connects to the input of a current regulator and aswitch having a single input pole and a plurality of output polescorresponding to a plurality of resistors, wherein the current regulatoris a constant current controller that provides a regulated current forpowering a light emitting diode.